Implications of heat shock proteins and molecular chaperones on animal coronavirus infections: the lessons from bats.

Animal coronaviruses (CoVs) represent useful models of studying how CoVs cross the species barriers, adapt to various host species and modify their pathogenic features or tissue tropism. Interactions between viruses and host cells during viral infections are extremely complex and viruses also depend on the chaperone machinery of host cells for correct viral protein folding and virion assembly. Thus, it is likely that alterations in heat shock protein (Hsp) expression in host cells are involved in virus–host interactions, given their essential roles as molecular chaperones in multiple cellular processes. A brief overview of the main recent findings and future perspectives concerning the preventive and/or therapeutic potential of modulating Hsp expressions during SARS-CoV-2 infection is presented. Based on the available literature data, alterations in Hsp expression appear to be involved in animal CoV infections, as far as porcine and poultry CoVs are particularly concerned. As well, the elevated basal Hsp expression observed in bats seems to be a bat-specific evolutionary adaptation that may have a substantial impact on their pathogen-host equilibrium and zoonotic potential. Changes in Hsp expression occurring in animal CoV infections may offer a unique opportunity for understanding the evolution of this large family of viruses. The constitutive heat shock response (HSR) of bats is also noteworthy, since HSR is the main biochemical pathway leading to the physiological resolution of inflammation and is physiologically induced by fever, thus offering a rationale for reconsidering the proper management of fever in high-risk COVID-19 patients.